Visible and near-infra-red laser devices have been used for many years to treat vascular and pigmented lesions. Over the last decade, flashlamps delivering controlled, intense broadband visible-to near-infrared light have gained acceptance for use in hair removal and treatment of various cosmetic skin conditions.
Common applications for flashlamp treatments include treatment of individual vascular and pigmented lesions including facial telangiectasias and cherry hemangiomas or solar lentigines. These types of target lesions are typically small or highly localized. Currently-used flashlamp devices typically deliver energy to the tissue through fairly large, rectangular optical apertures (i.e. where the waveguide has maximum transverse dimensions of approximately 10 by 30 mm, with minimum transverse dimensions of approximately 8-12 mm). When a large aperture device is used to treat small or localized lesions, unwanted side-effects can occur such as hypo and hyper pigmentation and crusting in the skin surrounding the lesion. “Postage stamp” side effects are common with standard rectangular aperture flashlamp devices and are a function of both the size and shape of the treatment area. Sometimes in an effort to minimize these side effects a portion of the optical aperture will be masked or blocked to limit energy delivery to only the treatment area. Specifically, masking objects or agents, such as Teflon tape, gauze or other physical barriers are interposed between the light aperture and the skin to produce specific shapes or small areas of exposure. Other procedures for delivering highly localized treatment attempt to limit the treatment area by relying on the selectivity of the target lesion or structure based on optical absorption characteristics, a technique that may not be optimal for treating patients having relatively dark colored skin.
It is desirable to provide an improved flashlamp device that allows treatment of individual lesions without effecting surrounding areas, without rectangular spot profiles and the associated side effects and to simplify localization of the contacting surface to the target area without sacrificing treatment speed, skin cooling ability, or optical efficiency.